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1.
Sci Total Environ ; 926: 171873, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38521275

RESUMO

Research on High Spatial-Resolved Source-Specific Exposure and Risk (HSRSSER) was conducted based on multiple-year, multiple-site synchronous measurement of PM2.5-bound (particulate matter with aerodynamic diameter<2.5 µm) toxic components in a Chinese megacity. The developed HSRSSER model combined the Positive Matrix Factorization (PMF) and Land Use Regression (LUR) to predict high spatial-resolved source contributions, and estimated the source-specific exposure and risk by personal activity time- and population-weighting. A total of 287 PM2.5 samples were collected at ten sites in 2018-2020, and toxic species including heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs) and organophosphate esters (OPEs) were analyzed. The percentage non-cancer risk were in the order of traffic emission (48 %) > industrial emission (22 %) > coal combustion (12 %) > waste incineration (11 %) > resuspend dust (7 %) > OPE-related products (0 %) ≈ secondary particles (0 %). Similar orders were observed in cancer risk. For traffic emission, due to its higher source contributions and large population in central area, non-cancer and cancer risk fraction increased from 23 % to 48 % and 20 % to 46 % after exposure estimation; while for industrial emission, higher source contributions but small population in suburb area decreased the percentage non-cancer and cancer risk from 38 % to 22 % and 39 % to 24 %, respectively.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Monitoramento Ambiental , Material Particulado/análise , Cidades , Hidrocarbonetos Policíclicos Aromáticos/análise , China/epidemiologia
2.
Environ Pollut ; 312: 120004, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35995293

RESUMO

This study aims at exploring size distribution, meteorological influence and uncertainty for source-specific risks of atmospheric particulate matter (PM), which can improve risk-mitigation strategies for health protection. Heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in PM2.5 and PM10 were detected in a Chinese megacity during 2011-2021. A new method named as PMFBMR, which combines the Positive Matrix Factorization, Bootstrapping, Mote Carlo and Risk assessment model, was developed to estimate uncertainty of source-specific risks. It was found that PAH risks concentrated in fine PM, while HMs showed high risks in both fine and coarse PMs. For PM2.5, HQ (non-cancer risk hazard quotient) of gasoline combustion (GC), diesel and heavy oil combustion (DC), coal combustion (CC), industrial source (IS), resuspended dust (RD) and secondary and transport PM (ST) were 0.6, 1.4, 0.9, 1.6, 0.3, and 0.3. ILCR (lifetime cancer risk) of sources were IS (9.2E-05) > DC (2.6E-05) = CC (2.6E-05) > RD (2.2E-05) > GC (1.7E-05) > ST (6.4E-06). PM2.5 from GC, DC, CC and IS caused higher risks than coarse PM, while coarse PM from RD caused higher risks. Source-specific risks were influenced not only by emissions, but also by meteorological condition and dominant toxic components. Risks of GC and DC were usually high during stable weather. Some high risks of CC, IS and RD occurred at strong WS due to transport or wind-blown resuspension. GC and DC risks (influenced by both PAHs and HMs) showed strong relationship with T, while IS and RD risks (dominated by HMs) showed weak link with meteorological conditions. For uncertainty of source-specific risks, HQ and ILCR were sensitive for different variables, because they were dominated by components with different uncertainties. When using source-specific risks for risk-mitigation strategies, the focused toxic components, used toxic values, PM sizes and uncertainty are necessary to be considered.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , China , Carvão Mineral , Poeira/análise , Monitoramento Ambiental/métodos , Gasolina , Metais Pesados/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Incerteza
3.
Environ Sci Pollut Res Int ; 29(52): 79002-79015, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35704234

RESUMO

PM2.5 samples collected over a 1-year period in a Chinese megacity were analyzed for organic carbon (OC), elemental carbon (EC), water-soluble ions, elements, and organic markers such as polycyclic aromatic hydrocarbons (PAHs), hopanes, steranes, and n-alkanes. To study the applicability of organic markers in source apportionment, the relationship between organic and inorganic components was analyzed, and four scenarios were implemented by incorporating different combinations of organic and inorganic tracers. The consistent temporal variations trend of 4-ring PAHs and SO42- prove that coal burning directly emits a portion of sulfate. The concentrations of ∑5-7-ring PAHs, NO3-, and NO2 show a trend of simultaneous increase and decrease, implying collective impacts from the vehicle source. The concentrations of OC and EC positively correlate with the 5-7-ring PAHs and Cu and Zn, which proves that part of Cu and Zn comes from vehicle emissions. Five factors were identified by incorporating only conventional components, including secondary source (SS, 30%), fugitive dust (FD, 14%), construction dust (CD, 4%), traffic source (TS, 19%), and coal combustion (CC, 14%). Six factors were identified by incorporating conventional components and PAHs, including SS (28%), FD (15%), CD (4%), CC (13%), gasoline vehicles (GV, 12%), and diesel vehicles (DV, 10%). Eight factors were identified by incorporating conventional components, PAHs, hopanes, and n-alkanes, including SS (26%), FD (17%), CD (3%), GV (14%), DV (8%), immature coal combustion (ICC, 5%), mature coal combustion (MCC, 10%), and biogenic source (BS, 1%).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Hidrocarbonetos Policíclicos Aromáticos , Emissões de Veículos/análise , Material Particulado/análise , Poluentes Atmosféricos/análise , Estações do Ano , Poluição do Ar/análise , Gasolina , Dióxido de Nitrogênio , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Carvão Mineral/análise , Poeira/análise , Carbono/análise , Água , Alcanos , Sulfatos , Triterpenos Pentacíclicos
4.
Arch Med Sci ; 17(4): 1044-1055, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34336032

RESUMO

INTRODUCTION: This study aimed to investigate the role of microRNA (miRNA) that affects acute myelocytic leukemia (AML) and its potential molecular mechanism by constructing a miRNA-mRNA interaction network using bioinformatics methods. MATERIAL AND METHODS: MicroRNA expression data of AML were retrieved from Gene Expression Omnibus (GEO) and analyzed by microarray analysis. Expression levels of miR-107 and RAD51 mRNA were detected by quantitative real time polymerase chain reaction (qRT-PCR). Protein expression of RAD51, pro-apoptotic protein Bax, apoptosis related protein CytC and anti-apoptotic protein Bcl-2 were determined by Western blot. The rate of cell apoptosis was detected by Annexin-V/PI. The predicted targeting relationship between miR-107 and the 3'UTR of RAD51 was first predicted by the online application TargetScan and then verified by dual-luciferase assay. RESULTS: Acute myelocytic leukemia-associated genes (n = 197) and miRNAs (n = 1701) were retrieved from the database, the interaction network of miRNA-mRNA was constructed and the core position was occupied by RAD51. miR-107 exhibited a regulatory effect on RAD51 in which the mRNA and protein expression of RAD51 were both significantly inhibited by miR-107 mimics in vitro. Additionally, down-regulated expression of miR107 as well as up-regulated expression of RAD51 were detected not only in the plasma of AML patients compared to healthy volunteers, but also in AML cell lines compared to the normal bone marrow stromal cell line. Further study found that increased expression of miR-107 and the consequent down-regulation of RAD51 could aggravate the apoptosis of AML cells in vitro. CONCLUSIONS: Our present results showed that the crucial role of RAD51 and miR-107 in the apoptosis of AML cells, i.e., miR-107 promotes the apoptosis of AML cells through down-regulating the expression of RAD51.

5.
Environ Int ; 146: 106162, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069984

RESUMO

Synchronous heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) in inhalable particulate matter (PM10) were measured during 2009-2012 and 2015-2016 in a Chinese megacity (Chengdu) to understand the variations in source-specific health risks during haze episodes. Samples were divided into four mass concentration levels: PM10 ≤ 150 µg m-3 (L1), 150 µg m-3 < PM10 ≤ 250 µg m-3 (L2), 250 µg m-3 < PM10 ≤ 350 µg m-3 (L3), and PM10 > 350 µg m-3 (L4). The percentages of some HMs and PAHs (accounting for PM10) decreased from L1 to L4, indicating that they exhibited lower growth rates than other species during heavy pollution. The combined cancer risk (R) for HMs and PAHs was higher at L1 and L4, and the combined non-cancer risk (HQ) was significantly high at L4. The HMs and PAHs combined source-specific risk apportion (HP-SRA) model was employed to quantify the source-specific risks. The relative contributions of (i) diesel and gasoline vehicles to the R, and (ii) crustal dust to the HQ increased during heavy pollution (L3 and L4). The relative contribution of industrial source declined from 81% (L1) to 60% (L4) for the HQ, and from 49% (L1) to 36% (L4) for the R, implying that the control of industrial emissions during heavy pollution events could alleviate risk growth as a co-benefit of controlling PM mass concentration. However, the risks associated with industrial emissions should also be considered during 'clean' days.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Monitoramento Ambiental , Metais Pesados/análise , Metais Pesados/toxicidade , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Medição de Risco , Emissões de Veículos/análise , Emissões de Veículos/toxicidade
6.
Huan Jing Ke Xue ; 41(10): 4455-4461, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124377

RESUMO

As flue gas desulfurization (FGD) was one of the most important purification processes of coal-fired boilers, we selected four boilers, which were equipped with wet limestone, furnace calcium injection, ammonia-based, and double-alkali FGDs, to research the influence of FGDs on the flue particulate matter (PM). The flue PM before and after the FGD were sampled using laboratory resuspension and dilution tunnel sampling methods, respectively, and the PM was analyzed for its chemical composition (i.e., ions, elements, and carbon). The results showed that the types of desulfurizers could influence the composition of the flue PM. After passing through the wet limestone, ammonia-based, and double-alkali FGDs, the proportion of Ca, NH4+, and Na in PM2.5 increased from 5.1% to 24.8%, from 0.8% to 7.3%, and from 0.9% to 1.7%, respectively. The influence of wet and dry FGDs on the flue PM were different. The fraction of ions in the PM emitted from the wet FGD were higher than those from the dry FGD. The proportion of SO42- in the flue PM2.5 increased from 2.0% and 6.7% to 9.6% and 11.9% using the wet limestone and ammonia-based FGDs, respectively, and Cl- increased from 0.4% and 1.2% to 3.8% and 5.2%. In addition, the amount of heavy metals (e.g., Cr, Pb, Cu, Ti, and Mn) in PM2.5 declined after the wet FGDs. The PM2.5 emitted from the dry FGD boiler was richer in crustal elements, such as Al, Si, and Fe, than that from the wet FGDs. The wet FGDs also effected the carbonaceous components of the flue PM. After passing through the wet limestone and ammonia-based FGDs, the proportion of elemental carbon in the flue PM2.5 decreased from 6.1% to 0.9% and from 3.6% to 0.7% respectively, but the organic carbon content did not decrease.

7.
Environ Sci Pollut Res Int ; 27(36): 45824-45835, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803594

RESUMO

Post-combustion flue gas desulfurization and denitrification technologies are essential in achieving the full compliance of fine particulate matter (PM2.5, aerodynamic diameter less than 2.5 µm) air quality standards by 2030 in China as sulfur dioxide (SO2) and nitrogen oxides (NOX) are the main precursors of PM2.5. Some studies have addressed the performance evaluation of desulfurization technology, but none included the water-soluble ions (sulfate (SO42-), nitrate (NO3-), etc.) as an indicator nor accounted for uncertainty involved. In this study, we present a multilevel fuzzy method that integrates the analytic hierarchy process with fuzzy theory, defines SO42-concentration as a new environmental indicator, and is supplemented with an uncertainly analysis and apply the method for the techno-economic and environmental evaluation of desulfurization and denitrification technologies in six typical enterprises (including two power plants and three industrial production plants and a waste incineration plant) in Chengdu, China. The evaluation shows that first, the fluctuating desulfurization rate and the dosage leads to changed ranking of the economic and technical secondary evaluation results, with the overall comprehensive evaluation ranks unchanged. Second, from the perspective of environmental protection agency and the public, if the environmental indicators are empowered, the lower the SO42-concentration of an enterprise, the better its evaluation ranking will be and vice versa. Third, if we re-empower from the perspective of the enterprise, under the condition that the technical feasibility is met and the environmental indicators are basically up to standard, the low-cost removing process is more likely to be the tendency of the enterprise. In summary, the findings of the study have led to the conclusions that (1) for the power industry, the integration of desulfurization, denitrification, and dedusting technologies should be promoted rigorously; (2) the non-power industry should continue the end-of-pipe treatment and environmental protection regulatory policies of the power industry; and (3) the energy industry structure should be optimized with enhanced end-of-pipe control technologies to achieve deep reduction of air pollutants.


Assuntos
Poluentes Atmosféricos , Desnitrificação , Poluentes Atmosféricos/análise , China , Material Particulado/análise , Dióxido de Enxofre/análise
8.
Front Pediatr ; 8: 349, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32676490

RESUMO

Objective: To identify postnatal risk factors for bronchopulmonary dysplasia (BPD) development in preterm infants with gestational age ≤32 weeks. Methods: Seventy-two preterm infants(30 with BPD and 42 non-BPD controls) admitted in the neonatal intensive care unit (NICU) of the Children's Hospital of Soochow University during 2017 were enrolled in this prospective longitudinal study. Perinatal clinical data, a neonatal critical illness score (NCIS), different soluble B7-H3(sB7-H3), and interleukin-18 (IL-18) levels by days after birth were collected. An early predictive model for BPD development was established based on clinical data using multiple logistic regression analysis. And the sensitivity and specificity of the model were assesed by ROC curve. Results: Electrolyte disturbances, hemodynamically significant patent ductus arteriosus (hs-PDA), and the age that infants achieved 120 kcal/kg.d via enteral feeding ≥40 days after birth were found to be associated with the BPD pathogenesis. Serum sB7-H3, IL-18, and NCIS were significantly higher in the BPD group compared to the non-BPD group (p < 0.05). BPD group had significantly lower enteral fluid and caloric intake compared to the non-BPD group at 1, 7, 14, and 28 days after birth. The risk factors were analyzed by multiple logistic regression and a predictive model of a combination of sB7-H3 (day 7), IL-18 (day 14), NCIS, and clinical risk factors was evaluated via ROC curve with an area under the curve (AUC) of 0.960 having sensitivity of 86.7% and a specificity of 97.6%, respectively. Conclusion: The causes of BPD are multifactorial postnatal risk factors. And the combination of sB7-H3 (day 7), IL-18 (day 14), NCIS, and clinical risk factors (electrolyte disturbances, hs-PDA, and the age that infants achieved 120 kcal/kg.d via enteral feeding ≥40 days after birth) might be served as an optimal predictive model for the occurrence of BPD.

9.
Huan Jing Ke Xue ; 40(9): 3949-3961, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854857

RESUMO

The characteristics of volatile organic compound (VOCs) species from various production procedures of wood-based panel production and other industrial processes in Chengdu were analyzed through gas chromatography-mass spectrometry (GC-MS) and other methods specified in national standards after the emissions of typical enterprises of wood-based panel production, pharmaceutical manufacturing, chemical production and other industrial processes in Chengdu had been sampled using sampling bottles and SUMMA canisters. Generally, the process of wood-based panel production includes glue making, glue mixing, sorting, and hot pressing, whereas the process of pharmaceutical manufacturing includes workshop production and wastewater treatment. The results showed that the main contribution species of VOCs in wood-based panel production and pharmaceutical manufacturing is oxygenated VOCs (OVOCs), accounting for more than 50% of the total VOCs emitted. The species from organized and unorganized emissions of formaldehyde manufacturing differed significantly. The main species of organized emissions was OVOCs, and that of unorganized emissions was halohydrocarbons. Emissions of VOCs from coating manufacturing were strongly correlated with the raw materials, and the corresponding emission species were composed mainly of aromatics and OVOCs. Except for glue mixing, the main species of VOCs in other process procedures of wood-based panel production was formaldehyde, with emission proportion of more than 50%. The primary species of VOCs in various processes of pharmaceutical manufacturing was ethanol; however 1,4-dioxane, ethyl acetate, and toluene were also important species. Moreover, the main VOCs from formaldehyde manufacturing were composed mainly of acetone and ethanol, and those of coating manufacturing were aromatic hydrocarbons such as p-xylene. The ozone formation potential was to characterize the reactivity of pollution sources in VOCs from wood-based panel production, pharmaceutical manufacturing, and chemical production. The results showed that the species of VOCs in different industries contributed similarly to the reactivity and that these species were mainly high-activity species such as formaldehyde, ethanol, and other OVOCs as well as some aromatic hydrocarbons. Therefore, supervision and regulation of enterprises of industrial processes is required with a focus on species with relatively large ozone formation potential. In addition, it is necessary to analyze the emission characteristics and chemical mechanism of various industries and to control O3 generation from the sources.

10.
Ecotoxicol Environ Saf ; 186: 109740, 2019 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-31655327

RESUMO

To comparatively analyze source-specific risks of atmospheric particulate matter (PM), PM10-bound polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) were synchronously detected in a megacity (Chengdu, China) from 2009 to 2016. Non-cancer risk (assessed by hazard quotient, HQ) of PAHs and HMs was within the acceptable level, while cancer risk (assessed by incremental life cancer risk (ILCR), R) of PAHs and HMs were 1.01 × 10-4 and 9.40 × 10-5 in DP and WP, which showed low risk. HMs dominated cancer (92.12%) and non-cancer (99.99%) risks. An advanced method named as joint source-specific risk assessment of HMs and PAHs (HP-SRA model) was developed to assess comprehensive source-specific risks. Gasoline combustion (contributed 9.6% of PM10, 0.3% of HQ and 10.0% of R), diesel combustion (6.2% of PM10, 0.2% of HQ and 10.7% of R), coal combustion (17.5% of PM10, 1.8% of HQ and 13.4% of R), industrial source (9.1% of PM10, 80.7% of HQ and 35.0% of R), crustal dust (28.1% of PM10, 9.0% of HQ and 1.6% of R), nitrate (7.5% of PM10, 1.1% of HQ and 6.2% of R) and sulphate & secondary organic carbon & adsorption (SSA, 19.6% of PM10, 6.9% of HQ and 23.1% of R) were identified as main sources. For cancer risk, industrial sources and SSA posed the highest proportion. Higher levels of Co and Ni generated from industrial sources and Cr (Ⅵ), Cd and Ni absorbed in the SSA can result in high-risk contributions. Thus, controlling HMs levels in industrial emissions is essential to protecting human health.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metais Pesados/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Atmosféricos/química , China , Cidades , Humanos , Metais Pesados/química , Tamanho da Partícula , Material Particulado/química , Hidrocarbonetos Policíclicos Aromáticos/química , Medição de Risco
11.
Huan Jing Ke Xue ; 40(4): 1613-1626, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087901

RESUMO

Based on the measured data in the literature, VOCs (volatile organic compounds) source profiles were revised and reconstructed without OVOCs (oxygenated volatile organic compounds) species to obtain the normalized VOCs source profiles. Using the 2015 Sichuan emission inventory, source profiles based on the 1 km×1 km gridded speciated VOCs emission inventory were developed, and the ozone formation potentials of the species were estimated to assess the environmental impact on ozone formation. The established VOCs source profile database consists of 45 source profiles and 519 species. Since the source profiles were established based on the revision and reconstruction of pollution sources, such as biomass burning and transportation, that are rich in OVOCs, the source profile database is better applicable to establishing the speciated VOCs emission inventory and source apportionment. The speciated VOCs emission inventory showed that the total anthropogenic emission of VOCs in Sichuan Province was 773.8 kt, of which the emissions of alkanes, olefins, alkynes, aromatics, OVOCs, halohydrocarbons, and other VOCs accounted for 21.6%, 10.0%, 1.7%, 28.0%, 26.2%, 4.2%, and 8.3% of the total respectively. The total OFP (Ozone formation potential) was 2584.9 kt, of which the OFPs of the VOCs groups mentioned above accounted for 6.9%, 26.1%, 0.5%, 42.3%, 23.2%, 0.4%, and 0.5% respectively. The main VOCs species emitted in all cities of Sichuan Province were aromatics, OVOCs, and alkanes; however, there were some significant regional differences:transportation in Chengdu, Ya'an, Aba, Ganzi, and Liangshan made a greater contribution to VOCs emissions, with alkane emissions accounting for a higher proportion in the total VOCs emission. As a heavy industrial city, Panzhihua suffered most from emissions from industrial processes, which contain a relatively high proportion of alkanes. Solvent use in Deyang, Meishan, Suining, and Ziyang made a great contribution to the VOCs emissions, and the OVOCs emission was relatively high. Emissions of VOCs and species with relatively high OFPs in Sichuan Province were mainly distributed in the Sichuan Basin, which has a dense population and highly developed industry, as well as some areas in Liangshan and Panzhihua. The main source of m-xylene and toluene was solvent use; therefore, m-xylene and toluene were relatively concentrated in developed urban areas. In addition, biomass burning contributed greatly to the emissions of ethene and formaldehyde; therefore, ethene and formaldehyde were mainly distributed in the cultivated areas of agriculturally advanced Eastern Sichuan and Southern Sichuan.

12.
Front Physiol ; 9: 1697, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30555341

RESUMO

Aphidius gifuensis Ashmead (Hymenoptera: Aphidiidae) is a solitary endoparasitoid used in the biological control of various aphids. Diapause plays an important role in the successful production and deployment of A. gifuensis. Diapause can effectively extend the shelf life of biological control agents and solve several practical production problems like long production cycles, short retention periods, and discontinuities between supply and demand. In recent years, studies have been conducted on the environmental regulation and physiological and biochemical mechanisms of diapause in A. gifuensis. Nevertheless, the molecular mechanism of diapause in this species remains unclear. In this study, we compared the transcriptomes and proteomes of diapause and non-diapause A. gifuensis to identify the genes and proteins associated with this process. A total of 557 transcripts and 568 proteins were differentially expressed between the two groups. Among them, (1) genes involved in trehalose synthesis such as glycogen synthase, glycogen phosphorylase, and trehalose 6-phosphate synthase were upregulated in diapause at mRNA or protein level while glycolysis and gluconeogenesis-related genes were downregulated, suggesting that A. gifuensis stores trehalose as an energy resource and cryoprotectant; (2) the expression of immune-related genes like C-type lectins, hemocyanin, and phenoloxidase was increased, which helps to maintain immunity during diapause; (3) a chitin synthase and several cuticular protein genes were upregulated to harden the cuticle of diapausing A. gifuensis larval. These findings improve our understanding of A. gifuensis. diapause and provide the foundation for further pertinent studies.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 607-11, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30292180

RESUMO

In order to research the effect of X-ray fluorescence (XRF) analysis on the results in the sample's micro particles, MCNPX models had been established for an X-ray fluorescence analyzer in this paper. It had studied the characteristics of the samples with different particle sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios. A micro particle analysis experiment had been designed for its verification. The results showed that: as for the relationship between the fluorescence intensity and the particle sizes, the MCNPX calculations were consistent with the theoretical, but contrary with the experimental results; the reason is that some hypotheses about samples in the MCNPX models were contrary with the actual states; the samples were crushed by grinding to small particles and tableting process, the MCNPX calculations and experimental results can be conversion; when the particle sizes of the samples reached the certain sizes, the fluorescence peak counts, the peak to total ratios and the peak to source ratios were stable value; within a particular size range, the influence of the particle size effects cannot be ignored, otherwise this influence can be ignored. The research methods and conclusions in this paper can provide a technical reference guide for X-ray analysis in practices.

14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 16(3): 525-30, 2008 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-18549622

RESUMO

This study was aimed to explore the expression level of the unknown cgi-100 gene in human leukemia K562 cells treated with matrine, and to investigate effect of cgi-100 on proliferation of K562 cells. The expression level of cgi-100 was detected by RT-PCR in K562 cells before and after being treated with matrine; pIRES2-EGFP/cgi-100 eukaryotic expression vector was constructed by DNA recombinant technique and was introduced into K562 cells by liposome-mediated DNA transfection. The cgi-100 gene expression level, growth-curve, and cell cycle of the modified K562-cgi-100 cells were detected by RT-PCR, Trypan blue staining and FCM. Morphological changes were observed under the optical and electron microscopes. The results indicated that the expression level of cgi-100 decreased in K562 cells treated with matrine. Heterochromatin decreased, euchromatin and the proportion of S phase in K562-cgi-100 cells increased, and cell proliferation enhanced. It is concluded that the expression of cgi-100 mRNA decreased in a dose- and time-dependent manner in the K562 cells treated with matrine and over-expression of cgi-100 elevates the proliferation and the immaturity level of K562-cgi-100 cells.


Assuntos
Alcaloides/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Genes Neoplásicos/genética , Quinolizinas/farmacologia , Regulação Neoplásica da Expressão Gênica , Genes Neoplásicos/fisiologia , Humanos , Células K562 , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Matrinas
15.
Zhonghua Xue Ye Xue Za Zhi ; 28(12): 823-7, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18476594

RESUMO

OBJECTIVES: To investigate the expression status of IER3IP1 gene during matrine induced K562 cell differentiation, and to figure out the function of IER3IP1 gene in K562 cell line. METHODS: Trypan-blue staining was used to analyze the growth inhibitory effect of matrine on K562 cells. Semi-quantitative RT-PCR was employed to investigate the expression status of IER3IP1 gene treated with different time and dosage of matrine. The alteration of cellular morphology, cellular proliferation and ultra-microstructure were observed and the cell cycle was detected on the recombinant IER3IP1 gene eukaryotic expression vector eYFP-IER3IP1 plasmid transfected K562 cells (K562/eYFP-IER3IPl). RESULTS: Matrine inhibited the growth of K562 cells and reduced the expression of IER3IP1 gene. The expression level of IER3IP1 gene was transiently increased to three-to-four times in a dose-dependent manner after treated with matrine for 2 - 3 hours. Then, in 6-48 hours it maintained at a low level as compared with the control group. The proliferation rate of the K562/eYFP-IER3IP1 cells significantly slowed down with more cells blocked in G0-G1 phase (P < 0.05). The number of erythroid blast cells began to increase after 24 hours of matrine treatment. At the same time, differentiated erythroid cells could be observed. CONCLUSIONS: Matrine can inhibit the growth of K562 cells, and transiently increase the expression level of IER3IP1 gene in a dose-dependent manner. The sensitivity of K562 cells to matrine maybe increased after being transfected by the eYFP-IER3IP1 plasmid, indicating a possible involvement of the IER3IP1 gene in the early response of the cells to matrine and its possible role in the erythroid cell differentiation.


Assuntos
Alcaloides/farmacologia , Proteínas de Transporte/metabolismo , Proteínas de Membrana/metabolismo , Quinolizinas/farmacologia , Proteínas de Transporte/genética , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , Células K562 , Proteínas de Membrana/genética , Matrinas
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